ID:1848463
 
(See the best response by Kaiochao.)
Is it possible to set area's default icon to transparent to get rid of black default background or is this permanent? It breaks the illusion of something I want to do.

What else would I need to do to have a completely invisible background?

You know those square dots that give no color.
Best response
/areas by default have no icon. The black background is the default background color of your Map interface element, which can be changed to any color.

What exactly do you want to see instead of black? If you want the gray checkerboard, you'll need a gray checkerboard icon, because it's not actually transparent. If you want your window to actually be transparent, you can do that with the transparency mask in the window options in the skin editor.
Alright thanks.